Apparatus for receiving sheets cut from a web

ABSTRACT

This apparatus for receiving sheets cut from a web comprises only mechanical means for retarding and braking the successive cut sheets so that they overlap one another before being delivered. This apparatus comprises downstream of the rotary cutter at least one upper cylinder and a lower cylinder, said upper cylinder having on one portion of its outer peryphery at least one peripheral boss having a cylindrical contour, engageable in at least one recess of same radius formed in the lower cylinder.

3,685,823 1 Aug. 22, 1972 United States Patent Chambon 11/1941Matthews...................

2,261,972 .271/76 3,034,780 Stelling........................271/46 [54]APPARATUS FOR RECEIVING SHEETS CUT FROM A WEB Primary Examiner-RichardE. Aegerter Alt0rney-Robert E. Burns et al.

ciales, Paris, France [22] Filed: July 7, 1970 ABSTRACT This apparatusfor receiving sheets cut from a web Appl. No.1 52,788

[30] Foreign Application Priority Data July 11, 1969 comprises onlymechanical 'means for retarding and- France......................6923774braking the successive cut sheets so that they overlap one anotherbefore being delivered.

Int. Cl-

appa atus omprises downstream of the rotary Field ofSearch......r..27l/46, 76, 77,DlG. 8, 69, cutter at least one uppercylinder and a lower cylinder, said upper cylinder having on one portionof References Cited its outer peryphery at least one peripheral bosshaving UNITED STATES PATENTS a cylindrical contour, engageable in atleast one recess of same radius formed in the lower cylinder.

1,752,648 4/1930 Matthevvs....................271/76 4 Claims, 1 DrawingFigure APPARATUS FOR RECEIVING SHEETS CUT FROM A WEB BACKGROUND OF THEINVENTION The present invention relates to an apparatus for receivingsheets cut from a web. 7

Apparatus designed for'receiving successive sheets cut from a web on anendless conveyor belt are already known; these cut sheets overlap oneanother somewhat like the tiles of a roof.

These apparatus utilize as a rule air-pervious movable supports such asrotary drums or perforated belts through which an air suction isproduced in order to press the sheets by suction against these supports.It is thus possible to slow down one sheet in relation to the next sheetso that the various sheets eventually received on a conveyor belt drivenat a relatively low speed overlap one another.

Thus, the US. Pat. No. 2,580,469 describes an apparatus for receivingflat articles cut from a continuous web by means of a rotary cutter soas to form a row of sheets on a discharge conveyor comprising,downstream of the cutter, an upper cam and a lower cam and a lower cammounted for rotation about two transverse shafts respectively, the cutarticles being adapted to move between these cams, the upper cam havinga gradually decreasing radius; the cam with the increasing radius has alower coefficient of friction than that of the cam having the decreasingradius, whereby the article is carried along by said lower cam. Meansare provided for rotatably driving said cams in opposite directions at aspeed such that the tangential speed of the lower cam be equal to thelinear speed of the article at the time of its engagement. After thisengagement has occurred, the article is slowed down, lowered in relationto the next article issuing from the cutter and eventually laid upon adischarge conveyor. Feed rollers are arranged upstream of the cutterdevice and driven at a tangential speed' equal to the linear speed ofthe cut articles. The aforesaid cams are operatively interconnectedthrough pinions and also connected through trains of gears or a chaintransmission to said feed rollers and to said rotary cutter.

SUMMARY OF THE INVENTION The apparatus according to the presentinvention is advantageous notably in that each sheet is positivelyprevented from abutting against the trailing edge of the precedingsheet; in the other hand, this apparatus does not comprise any rotarymember in which an internal suction is produced.

This invention is characterized in that the apparatus constituting thesubject-matter thereof, for receiving sheets cut from a web by a rotarycutter and depositing upon a discharge conveyor a succession of sheetswherein each sheet partially overlaps the preceding one, comprisesdownstream of said rotary cutter at least one pair of transversecylinders consisting of an upper cylinder and a lower cylinder formingtherebetween a passage through which the cut sheets are adapted to movewith a minimum clearance, said upper cylinder comprising on one portionof its outer periphery at least one cylindrical boss or projectionconcentric to said upper cylinder, said lower cylinder comprising, onone portion of its outer periphery, at least one recess formed with acylindrical bottom coaxial to said lower cylinder, both cylinders beingrotatably driven in opposite directions so that during this movement thecylindrical boss'of said upper'cylinder engages tangentially saidcylindrical'bottom surface of said recess formed in said lower cylinderand at a same linear speed of same direction as the feed rate of the cutsheets andlower than this speed each time the trailing edge of a cutsheet travels between said cylindrical boss of said upper cylinder andsaid cylindrical bottom of the recess formed in said lower cylinder.

BRIEF DESCRIPTION OF THE DRAWING DESCRIPTION OF THE PREFERRED EMBODIMENTThe apparatus according to this invention is designed for receivingsheets cut from a continuous web ,1 consisting, for example, of paper,although the invention is not limited to this specific material. Thesheets are cut by means of a rotary cutter 2 known per se arrangedupstream of the apparatus and comprising essentially a blade 3 rotatablyrigid with a shaft 4 and adapted to coact with a counter-blade 5. Theshaft 4 is rigid with a pinion 6 and rotatably driven at a speeddepending of course on the format or size of the cut sheets, from apower pinion 7, through a pair of lay pinions 8 and 9.

Each time the movable cutter blade 3 engages the fixed lowercounter-blade 5, it cuts a sheet from the web 1 and the cut sheet 1a iscarried along, downstream of the cutter between idle upper feed rollers11 and driven lower feed rollers 12. These feed rollers 12 are rotatablydriven from a device to be described presently at a tangential speedslightly greater than the tangential speed of the rotary cutter whichcorresponds to the size of the cut sheet, so that the rollers 11 and 12produce a slight relative spacing between the successive cut sheets.

The sheet receiving apparatus according to this invention comprisesdownstream of the cutter 2, a slowdown device designated as a wholeat l3and comprising essentially a set of upper cylinders 14 rigid with atransverse horizontal shaft 15, and a set of lower cylinders l6 rigidwith a transverse and horizontal lower shaft 17. The slow-down device 13also comprises an upstream feed device comprising upper idle rollers 18co-acting with lower driven rollers 19, and a downstream feed devicecomprising upper idle rollers 21 co-acting with lower driven rollers 22.The shaft 17 carrying the lower cylinders, 16 is rotatably rigid with apinion 23 meshing with another pinion 24 rigid with the shaft 15carrying the upper cylinders 14.

Pinion 23 is in constant meshing engagement with an intermediate or laypinion 25 meshing in turn with a pinion 26 rigid with a shaft 27carrying the lower rollers 19. This pinion 26 is also drivinglyconnected via pinion 28 to another pinion 29 rigid with a shaft 31carrying the lower driven rollers 12.

On the other hand, the aforesaid pinion23 is operatively connectedthrough an intermediate pinion 32 to another pinion 33 rigid with ashaft 34 carrying the lower driven rollers 22.

Finally, the same pinion 23 is drivingly connected to thepower pinion 7via a train of gears designated as a whole by the reference numeral 35.

The transmission ratios provided by the various pinions and gears are soselected that the lower feed 16, this. recess having a circular contourextending along an arc Cban'd having a radius R shorter than the radiusR of the remaining portion 16 b of cylinder 16. The distance betweencenters of shafts and 17 is twice the radius R of boss 14a and recess16a, so that at each revolution of cams 14 and 16 (revolving at the sameangular speed) the boss 14a engages the recess 16a and rolls thereonwithout slipping. A

As clearly shown in the drawing, the arc AB covered by the contour ofboss l4a cor,responds to about 30 and is definitely smaller than the arcCD along which extends the recess 16a (about 75). Between the cylinders14 and 16 and the upstream forwarding rollers 18,

19 and downstream feed rollers 21, 22, horizontal ta- This pinchingeffect takes place at a distance of,' say, 60 mm from the rear ortailing end of the sheet.

This pinching of sheet 1a between boss l4a and recess 16a takes placethroughoutthe rolling engagement between the boss'and the hollowcircular contour,

for instance along a peripheral distance of,,say, mm. I Since thetangential speeds of boss 14a and recess 16a are definitely lower thanthe linearspeed-of the sheets (for example the three-fourths of thisspeed), the

sheet 1a is braked or slowed down while the next sheet continues to bedriven at the tangential speed of rollers 18 and 19. Under theseconditions, an overlap of about 10 mm. is formed between the two sheets.

During the retaining action exerted on sheet 1a the downstream feedrollers21 and 22 slip while the up stream feed rollers 18 and 19 carryalong the next at the normal linear speed, thus permitting the desireddegree of overlap.

After a rotation of about 30 of the upper cam 14, the trailing edge B ofboss 14a leaves the recess 16a and the pinching action is discontinued.Thus,.sheet 1a is again carried along the tangential speed of downstreamfeed rollers 21 and 22, like the next sheet, thus perbles 30 and 36extend respectively, the sheets being adapted to slide on the topsurface of these tables. Table 36 has a comb-like extension 37 inclineddownwards and towards the earns 14 and 16, which fits inbetween theadjacent cams, as shown.

Finally, the sheet-receiving apparatusv according to this inventioncomprises at its outlet an endless conveyor belt 38 driven at a moderatespeed definitely lower than the linear speed of the sheets emerging fromthe feed rollers 21 and 22. r

The abovedescribed apparatus operates as follows:

when a sheet such asla has been separated from the.

web 1 by' the rotary cutter 2 it is carried along the feed rollers 21and 12, then by rollers 18 and 19, and finally by rollers 21 and 22. Infact, it passes freely between the cylinders 14 and 16 for at that timethe boss 14a of cam 14 is in its lower position and the recess 16a ofcam 16 is in its upper position. The cut sheet la may thus pass betweenthe cylindricalportion 14b (having the small radius R,) of cam 14 andthe portion 16b (of greater radius 8;) of cam 16, and is supported bythe latter during this passage.

When the rear or trailing portion of sheet In emerges from feed rollers18 and 19, the boss 14a of upper cylinder 14 engages the upper face ofcut sheet 1a, the

the circular contour 16a, the trailing edge of the sheet begins to bepinched between boss 14a and recess 16a.

mitting the overlap of the two successive sheets. Then, cam 16 holdswith its portion 16b the sheets between the two tables 30 and 36. v a

The sheets overlapping in the manner set forth' hereinabove are receivedbythe conveyor belt 38 which reduces their speed, thus permitting,during the pinching of the next sheet, of maintaining the" initialoverlap.

The apparatus according to this, invention may be utilized for 'a widerange of cut sheet sizes. In fact,it is only necessary to provide in themeans for rotatably driving the cylinders 14 and 16 a variable-speedtransmission mechanism permitting of adjusting at the pinching time aconstant ratio of the tangential speed corresponding to the cut size tothe tangential speed of boss 14a and recess16i1.

In the above-described form of embodiment of the invention each uppercylinder 14 carries only one boss 14a and similarly each lower cylinder16 has formed only one recess 16a therein, both cylinders revolving atthe same angular speed, so that a sheet'is pinched at each revolution.

According to a modified form of embodiment of this invention, the uppercylinder 14 may comprise a single boss 14a and the lower cylinder 16 maybe formed with a plurality of recesses 16a disposed at spaced angularintervals about its axis. In this case, the upper cylinder 14 of smallerradius than the lower cylinder 16 revolves at a greater speed so thatthe boss 14a of cam 14 and spaced intervals about its axis.'The lowercylinder 16.

having a smaller radius than upper cylinder 14 will thus rotate fasterthan this cylinder .14, whereby the various bosses 14a of upper cylinder14 engage the single recess 16a of lower cylinder 16 each time thelatter has accomplished a complete revolution What I claim is:

1. An apparatus for receiving sheets cut from a web by a rotary cutterand forming on a discharge conveyor a sequence of sheets wherein eachsheet partially overlaps the preceding one, which comprises, downstreamof the rotary cutter, at least one pair of transverse cylindersconsisting of an upper cylinder and a lower cylinder formingtherebetween a passage engaged with a small clearance by the cut sheets,said upper cylinder comprising on one portion of its outer periphery atleast one cylindrical boss coaxial to said upper cylinder, said lowercylinder comprising on the other hand along one fraction of its outerperiphery at least one recess formed with a cylindrical bottom surfaceconcentric to said lower cylinder, both cylinders being rotatably drivenin opposite directions so that during their movement of rotation thecylindrical boss of the upper cylinder engages tangentially thecylindrical bottom of the recess formed in said lower cylinder and at asame linear speed and in the same direction as the linear speed of saidcut sheet, but at a lower speed each time the trailing edge of a cutsheet passes between said cylindrical boss of said upper cylinder andsaid cylindrical bottom of said recess in said lower cylinder.

2. Apparatus according to claim 1, which comprises, upstream anddownstream of the passage between the 4 disposed upstream of saidpassage between said cylinders, a fourth train of gears operativelyconnecting said pinion rigid with said one cylinder to the feed rollersdisposed downstream of said passage between said cylinders and a pinioncoaxially rigid with the other cylinder and meshing with the pinionrigid with said first cylinder.

4. Apparatus as set forth in claim 2 andcomprising a horizontal tabledisposed with its upstream end downstream of said passageibetween thetwo cylinders, and a set of comb teeth'rigidly carried by said upstreamend and inclined downwards so as to extend into the outlet area of saidpassage between said cylinders.

1. An apparatus for receiving sheets cut from a web by a rotary cutterand forming on a discharge conveyor a sequence of sheets wherein eachsheet partially overlaps the preceding one, which comprises, downstreamof the rotary cutter, at least one pair of transverse cylindersconsisting of an upper cylinder and a lower cylinder formingtherebetween a passage engaged with a small clearance by the cut sheets,said upper cylinder comprising on one portion of its outer periphery atleast one cylindrical boss coaxial to said upper cylinder, said lowercylinder comprising on the other hand along one fraction of its outerperiphery at least one recess formed with a cylindrical bottom surfaceconcentric to said lower cylinder, both cylinders being rotatably drivenin opposite directions so that during their movement of rotation thecylindrical boss of the upper cylinder engages tangentially thecylindrical bottom of the recess formed in said lower cylinder and at asame linear speed and in the same direction as the linear speed of saidcut sheet, but at a lower speed each time the trailing edge of a cutsheet passes between said cylindrical boss of said upper cylinder andsaid cylindrical bottom of said recess in said lower cylinder. 2.Apparatus according to claim 1, which comprises, upstream and downstreamof the passage between the upper cylinder and the lower cylinder, pairsof feed rollers rotatably driven at a tangential speed equal to a samedriving speed.
 3. Apparatus according to claim 2, which comprises adrivIng pinion, a train of gears transmitting the drive from saiddriving pinion to said rotary cutter, another pinion coaxially rigidwith one of said cylinders, another train of gears operativelyconnecting said driving pinion to said pinion coaxially rigid with oneof said cylinders, a third train of gears connecting said pinioncoaxially rigid with said one cylinder to the feed rollers disposedupstream of said passage between said cylinders, a fourth train of gearsoperatively connecting said pinion rigid with said one cylinder to thefeed rollers disposed downstream of said passage between said cylindersand a pinion coaxially rigid with the other cylinder and meshing withthe pinion rigid with said first cylinder.
 4. Apparatus as set forth inclaim 2 and comprising a horizontal table disposed with its upstream enddownstream of said passage between the two cylinders, and a set of combteeth rigidly carried by said upstream end and inclined downwards so asto extend into the outlet area of said passage between said cylinders.